P1312: CHARACTERISTICS OF MEMBRANOUS NEPHROPATHY AFTER ALLOGENEIC HAEMATOPOIETIC STEM CELL TRANSPLANTATION
Authors: Yue Jin, Ye-Jun Wu, Xiao-Lu Zhu, Hai-Xia Fu, Yun He, Chen-Hua Yan, Yuan Kong, Feng-Rong Wang, Yuan-Yuan Zhang, Xiao-Dong Mo, Wei Han, Jing-Zhi Wang, Yu Wang, Huan Chen, Yu-Hong Chen, Xiang-Yu Zhao, Ying-Jun Chang, Lan-Ping Xu, Kai-Yan Liu, Xiao-Jun Huang, Xiao-Hui Zhang
Journal: HemaSphere (2023)

Topic: 22. Stem cell transplantation - Clinical Background: Allogeneic haematopoietic stem cell transplantation (allo-HSCT) is used to treat various blood diseases. Glomerular diseases after allo-HSCT are rare, and the most common disease is membranous nephropathy (MN) after allo-HSCT. The occurrence of MN is often accompanied by the clinical manifestations of cGVHD. In previous studies, the most common types of antibodies deposited in MNs after allo-HSCT were IgG1 and IgG4. Unlike primary MN, MN after allo-HSCT rarely represents a positive result for the PLA2R antibody. The main clinical manifestation of MN after allo-HSCT is an increase in urinary protein. Patients often seek medical treatment due to urinary protein or hypoalbuminemia. Symptomatic treatment, glucocorticoids and/or immunosuppressants (tacrolimus, cyclosporin, mycophenolate mofetil, rituximab, etc.) are given according to the severity of MN and the condition of the patients Aims: To describe the risk factors and outcomes of membranous nephropathy after allogeneic haematopoietic stem cell transplantation. Methods: In this retrospective study, we collected data from 29 cases of MN after allo-HSCT as diagnosed in our hospital and 1:3 matched a control group with the time of allo-HSCT as a reference. We collected the detailed HSCT information, laboratory examination results, renal pathological results, treatment methods and therapeutic effects from these patients to describe the risk factors, clinical characteristics and outcomes of membranous nephropathy after allo-HSCT. Results: In the univariate analysis, the age of the patient (P=.008), MDS (P=.045), HLA-matched related donor (MRD) (P=.001), HLA-matched unrelated donor (MUD) (P=.012), and history of cGVHD (P=.015) were the risk factors for MN after allo-HSCT. In the multivariate analysis, the risk factors for MN after transplantation were MRD (P=.001), MUD (P=.017), and history of cGVHD (P=.039). A detailed renal pathology was available in 26 of 29 patients. IgA, IgG, IgM, C1q, C3 and FRA immune deposits were detected in the glomerulus, among which IgG was the predominant immune deposit, with 19 patients presenting 3+ and 7 patients presenting 2+. IgG1 was the main IgG subtype, with 6 patients presenting 3+ and 10 patients presenting 2+, while IgG2, IgG3, and IgG4 could also be detected in some patients. In electron microscope pathology, the deposition sites of electronically dense substances of the glomerulus included the subepithelial, mesangium, subendothelial and basement membrane areas, among which the most common deposition site of electronically dense substances was the subcutaneous glomerulus. Four patients also presented with immune complex deposition in the renal tubules. The treatments for MN after transplantation included symptomatic treatment (sodium and water intake restriction, albumin, etc.), glucocorticoids and/or immunosuppressants (tacrolimus, cyclosporin, mycophenolate mofetil, rituximab, methotrexate, etc.). Thirteen of 29 patients achieved complete remission, 9 of 29 patients achieved partial remission, and 7 of 29 patients had no response to treatment. All the patients survived through the last follow-up. Summary/Conclusion: In this study, we analysed the risk factors for membranous nephropathy after allogeneic haematopoietic stem cell transplantation for the first time and described the clinical characteristics, treatment and outcomes. Keywords: Risk factor, Renal impairment, Allogeneic hematopoietic stem cell transplant, Outcome